Digital entertainment (DE) applications typically involve relatively extensive interaction between consumers and the media. In DE applications, therefore, media is often captured, edited, managed, rendered, and distributed. An example of a DE application is a video editing application, through which consumers annotate and modify the media. In other words, DE applications differ from traditional playback types of applications because of the level of interactivity provided to the consumers. As such, DE applications typically impact the media by adding a greater level of complexity, which ranges from labeling a certain video frame as a keyframe, but not changing the bit stream itself, to reproduction of the bit stream itself, such as splitting a media into multiple segments.
DE applications often need to access information embedded with media. For instance, a media is often rendered on different output devices, such as, a printer, a television, a high-definition television, and a computer monitor. In order to determine the optimal rendering strategy for each of these output devices, different applications request information pertaining to the media, such as, image aspect ratio and frame rate, at different points in time. As another example, in video editing and reproduction applications, many tasks, such as keyframe extraction, high resolution frame production, and panorama from multiple frames, require motion information among video frames as a required piece of information. As such, the motion information of the media is accessed frequently by the video editing and reproduction applications.
In DE applications, the media itself is often represented in a coded bit stream, such as MPEG-1 or MPEG-2, after being captured. These types of coded bit streams are the main forms of media representation in traditional media playback and media distribution applications, mainly due to certain advantages associated with their compression and transmission. However, in order to achieve the compactness that is required for compression and transmission of the coded bit streams, relatively complex schemes have been adopted to encode the digital media, to thereby generate the coded bit stream with relatively complicated data structures. The relatively complex coding mechanisms and coded bit streams often require sophisticated and complex mechanisms to access the information embedded in the coded bit streams.
Although these conventional methods of bit stream representation of digital media are suitable for general compression and decompression applications, they are inefficient for DE applications due, for instance, to their complex requirements on media objects.